This invention relates to a method for processing a light-sensitive silver halide color photographic material. More particularly, the present invention relates to a method for processing a light-sensitive silver halide color photographic material, which enables quick processing and generates little stain caused in a bleach-fixing step and which can provide improved processing stability in quick processing.
Recently, it has been desired, in the industry, to develop a technology which enables quick processing of a light-sensitive silver halide color photographic material and can provide stable or constant photographic performance of a processed photographic material.
Namely, a light-sensitive silver halide color photographic material is subtracted to running treatment by using an automatic developing machine provided in each laboratory for development. As a part of improved services for users or customers, it is required that a photograph should be printed and returned to a user or a customer within the day when a light-sensitive silver halide color photographic material to be developed is received. Recently, it is required even to return a printed material within several hours after receipt of a light-sensitive silver halide color photographic material to be developed. Thus, it has been in a hurry to develop a technology which enables quicker processing.
The prior art technologies concerning quick processing of a light-sensitive silver halide color photographic material may be classified roughly into the following art:
(1) technology relying upon the improvement of a light-sensitive silver halide color photographic material;
(2) technology relying upon physical means at the time of development processing; and
(3) technology relying upon the improvement of the composition of a processing solution used for development processing.
As concerns the above-mentioned art (1), there have been developed, specifically, .circle.1 a technology which has improved the composition of a silver halide (see, for example, a technology of forming fine grains of a silver halide as described in Japanese Provisional Patent Publication (KOKAI) No. 184142/1983, and a technology of reducing the silver bromide content in a silver halide as described in Japanese Patent Publication (KOKOKU) No. 18939/1981; .circle.2 a technology of using an additive (see, for example, a technology in which an 1-aryl-3-pyrazolidone having a specified structure as described in KOKAI No. 64339/1981 is added to a light-sensitive silver halide color photographic material and a technology in which a 1-arylpyrazolidone as described in KOKAI Nos. 144547/1982, 50534/1983, 50535/1983 and 50536/1983 is added to a light-sensitive silver halide color photographic material); .circle.3 a technology using a coupler having a rapid reactivity (see, for example, a technology using a yellow coupler having rapid reactivity as described in KOKOKU No. 10783/1976, and KOKAI Nos. 123342/1975 and 102636/1976); and .circle.4 a technology for providing a thinner film or layer which constitutes a photographic material [see, for example, a technology for providing a thinner film or layer which constitutes a photographic material as described in KOKAI No. 65040/1987 (Japanese Patent Application No. 65040/1987)].
As to the above-mentioned art (2), there is a technology of stirring a processing solution (see, for example, a technology of stirring a processing solution as described in Japanese Patent Application No. 23334/1986).
As to the above-mentioned art (3), there have been known .circle.1 a technology using a development accelerator, .circle.2 a technology of concentrating or thickening a color developing agent, .circle.3 a technology of lowering the halide ion (particularly, bromide ion) concentration in a processing solution, and so on.
Basically, the processing of a light-sensitive material includes two steps, i.e., a color development step and a desilverization step. The desilverization step includes a bleaching step and a fixing step or a bleach-fixing step. As additional processing steps other than the above, there may be added a rinsing treatment, a stabilizing treatment, a water-washing step or a stablizing step replacing the water-washing step and so on.
In color development, an exposed silver halide is reduced to silver and, at the same time, an oxidized aromatic primary amine series color developing agent is reacted with a coupler to form a dye. In the course of the reaction, halide ions which have been formed by the reaction of silver halides are dissolved into a developing solution and accumulated therein. Further, components such as a development inhibitor which have been contained in a light-sensitive material may also be dissolved out into a color developing solution and accumulated therein.
In the desilverization step, silver formed by the development is bleached by an oxidizing agent and then all the silver salts are removed as soluble silver salts by a stabilizing agent from a light-sensitive material.
It should be noted here that there has also been known a single-bath bleach-fixing process which carries out the bleaching step simultaneously with the fixing step.
In cases where a typical light-sensitive material is processed with a single-bath bleach fixing solution immediately after it is subjected to color development, the pH of such a bleach-fixing solution is usually maintained neutral (pH 7.0-7.5) or at a slightly higher value than neutral. In the case of a usual light-sensitive material, when the pH value is low, a Leuco dye is liable to be formed and a trouble which is referred to as so-called leuco dye formation is liable to occur. Therefore, the bleach-fixing solution is kept to be neutral or at a slightly higher pH value.
Among the quick processing technologies as mentioned above, it is the above-mentioned art (1) that is excellent in quick processing ability. And among the art (1), a method of using a light-sensitive silver halide color photographic material containing higher concentration of silver chloride (see, for example, KOKAI Nos. 95345/1983, 19140/1985 and 95736/1983) exhibits excellent quick processability.
However, when a light-sensitive silver halide photographic material containing silver halide grains having high concentration of silver chloride is subjected to continuous processing in a single-bath bleach-fixing solution having a pH value of 7.0-7.5 or of slightly higher value as in the case of a light-sensitive silver halide color photographic material comprising principally silver bromide, various components in a color developing solution are liable to accumulate in the bleach-fixing solution and hence stain is liable to occur on a processed light-sensitive material (referred to as "BF-stain" hereinafter).
Recently, there have progressed a technology of reducing the amount of a replenishing solution for a bleach-fixing solution and a technology of regenerating it in higher percentage from a view point of economy in the processing and reduction in amount of a waste processing solution. As the result, accumulation of various components in a color developing solution, in a bleach-fixing solution, is liable to increase and thus the problems of BF-stain and others have become remarkable.
In the present situation, these problems can not be solved only by such technologies as those known to the art, for example, those disclosed in KOKAI No. 136031/1975, and U.K. Pat. No. 1,131,335 and U.S. Pat. No. 3,293,036.
Further, according to the method of regeneration or the method of supplying smaller amount of concentrated replenishing solution, the composition of a processing solution may easily be influenced remarkably by evaporation and regenerating operation. The composition may also differ remarkably depending upon the amount of exposed photographic materials to be processed as well as the amount of evaporated processing solution and the amount of the replenishing solution. In particular, the amount of exposed photographic materials in a laboratory differs remarkably between at the beginning of a week when larger amount thereof is ordered to be developed by customers and at a week end when the amount of order decreases; and between at a high-season and at an off-season, the difference of the amounts appearing as a ratio of 1:5 at the maximum. Under such circumstances, such a photographic performance as fog becomes unstable.
Although it can not be said that there has not been any occurrence of BF-stain in a usual light-sensitive photographic material containing silver bromide as a main component, it has been found that this phenomenon becomes a serious problem in the case of a light-sensitive photographic material for the use of quick processing containing silver chloride as a main component.
It may be consided that the BF-stain is caused after a color developing agent itself is passed into the bleach-fixing bath and becomes an oxidized form such as a quinonediimine produced by an oxidizing agent such as ethylenediaminetetraacetic acid iron complex (EDTA-Fe) in the bleach-fixing bath and then the oxidized form is reacted in the bleach-fixing bath with a coupler in the light-sensitive color photographic material. Particularly, the BF-stain may remarkably be generated when the sulfite ion concentration in the color developing solution is low.
As a result of the present inventor's extensive study to solve the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by subjecting a light-sensitive silver halide color photographic material including a silver halide emulsion layer containing at least a certain amount of silver chloride to color development followed by processing in a combined bleach-fixing solution (or bath) having a certain range of pH values, and have accomplished the present invention.
Although there may be a problem that there is a possibility of occurrence of leuco dye formation phenomenon when the pH value of a bleach-fixing bath is low, if a light-sensitive silver halide color photographic material including a silver halide emulsion layer containing at least a certain proportion (80 mole % or more) of silver chloride is subjected to color development followed by processing with a bleach-fixing bath having a lower pH value of 4.5-6.8, then not only the leuco dye formation does not occur, but also BF-stain is difficult to occur even when various components in a color developing solution are accumulated by the continuous processing in a bleach-fixing bath, because of the rapid development rate of silver chloride.
Further, the development rate may further be enhanced by reducing the sulfite ion (SO.sub.3.sup.2-) concentration according to the above-mentioned art [3].
Furthermore, it was found that, by incorporating the color developing solution with an alkanol amine, the fog caused in the bleach-fixing solution could be suppressed and the generation of fog could be reduced even in the case when smaller amount of a replenishing bleach-fixing solution was supplied.
In addition, it was found that the above-mentioned BF-stain may further be reduced by using, as the color developing agent, a p-phenylenediamine series color developing agent, particularly a water-soluble p-phenylenediamine series color developing agent; and that even if BF-stain is caused less amount of the stain may be visualized in appearance by incorporating the color developing solution with a triazine series fluorescent-brightening agent.
Furthermore, it was found that the incorporation of a specific magenta coupler, a specific cyan coupler or a combination thereof in at least one layer of the silver halide emulsion layers in the light-sensitive silver halide color photographic material would enhance the stability during storage of the color developing solution, reduce the BF-stain caused by the bleach-fixing solution and provide an excellent photographic property at the maximum color density.